Flat knitting machines



Feb. 4, 1969 K. Esslc Y 3,425,245

FLAT KNITTING MACHINES Filed May 13. 1966 l5 l g l' 32 3| lill INVENTOR United States Patent O St 23,829 U.S. Cl. 66-64 Int. Cl. D04b 7/04, 15/70 S Claims ABSTRACT OF THE DISCLOSURE A multiple unit flat knitting machine has two or more knitting units arranged one behind the other or one.

behind and one beside another. The cam carriages of the units are driven by a common endless driving element which passes around two rotary guide components and is reci-procated lby drive means which enable both the length of stroke and the speed of travel of the cam carriages to 'be infinitely varied. A patterning arrangement common to all knitting units is associated with the drive means and influenced by the latter for effecting longitudinal displacements of and rendering operative and inoperative the control members which influence the knitting of the pieces of fabric being produced. The cam reversing elements are disposed in groups which are automatically adjustable in the longitudinal direction of the machine corresponding to the current length of the strokes. These elements are Ibrought into effective position through partial rotation of respective shifting rods, triggered by the patterning means.

This invention relates to flat knitting machines, and relates particularly to machines of the kind comprising two or several times two knitting units or sections.

By a knitting unit or section is meant a complete knitting entity including a needle bed or beds equipped with individually operable needles, a cam carriage which is fitted with one or more cam systems or locks and is traversable back and forth over the said bed or beds to operate the needles, and a yarn r thread guide or guides for supplying yarn to these needles.

One known form of flat knitting machines comprises merely what are in effect two substantially complete flat knitting machines, i.e., machines which are capable of operating alone as independent entities, arranged one beside another or one behind another and equipped with a common drive. Such a composite machine, however, is neither equipped with means for automatic operation nor with mechanism for automatically effecting desired variations in the width of the knitting and in the lengths of stroke and speed of travel of the cam carriages. Moreover, in the case of two fiat knitting machines arranged one behind the othervthere was and is the further disadvantage that, as viewed from the operators stand, the movements of the cam carriages take place not running in the same but in respectively opposite directions. As a general rule a piece of fabric knitted on a fiat machine is ordinarily started with a cam carriage movement from right to left, and thus for the production of identical or equal pieces of knitted fabric on a corresponding number of knitting units or sections, it is of considerable irnportance, if efficiency in operation is to be assured, that both or all of the cam carriages shall travel together in the same direction so that, therefore, each course on any one unit or section will be produced in the samedirection of movement as the corresponding course or courses simultaneously knitted on the other unit or section, or each of the other units or sections, as the case may be.

Furthermore it has already been proposed to provide Patented Feb. 4, 1969 a fiat knitting machine in which several cam carriages together with their cam plates or locks circulate in an elliptical or oval path. In a machine of this previously proposed form, it is, of course, possible to produce simultaneously several identical pieces of knitted fabric, with the cam carriages travelling in the same direction, ibut every course of knitting of every such piece of fabric is produced in the same direction. Patterning of the pieces thus is limited, or at least the required patterning can only be achieved with a loss of rational operation. That is to say, the freedom of patterning in this case is restricted, and hence fabric of the required quality or fashioning is difficult, if not impossible, to produce.

Generally it is an object of the present invention to provide a generally improved form of flat knitting machine of the kind herein referred to designed to obviate the foregoining disadvantages.

More particularly, an object of this invention is to provide a fiat knitting machine of the kind concerned in which not only are all the changes in the settings or conditioning of the various elements and components which determine shaping, variations in the stitch formation, the patterning, and the quality of the knitted fabric produced, automatically effected, but also the lengths of stroke and speed of travel of the two or mo-re cam carriages are infinitely variable automatically.

The improved flat knitting -machine of this invention generally is characterized in that two or more knitting units or sections are arranged one behind the other or one behind and one beside another, the cam carriages of the units or sections being drivable in the same direction of movement by virtue of their attachment to a common endless driving element which is passed around two rotary guide components and is movable 'back and forth by drive means so `constructed and operable as to enable both the length of stroke and the speed of travel of the cam carriages to be infinitely varied, and in that patterning means common to both or all of the knitting units or sections are associated with the drive means and inuenced by the latter for the purpose of effecting longitudinal displacements of and rendering operative and inoperative various control members or elements employed in the machine to influence the knitting of the pieces of fabric being produced.

In a preferred embodiment of the invention, elements provided for switching over, i.e., effecting reversal of cams in the cam systems or locks on the respective cam carriages, are disposed in groups which are automatically adjustable in the longitudinal direction of the knitting machine corresponding to the present length of the strokes. These elements are brought into an effective position through partial rotation of respective shifting rods, triggered by the patterning means.

It is, of course, already known in the art to provide, in a flat knitting machine wherein the strokes of the cam carriage are variable, rods which are disposed longitudinally of the machine and are operable to effect required adjustments of various reversing elements. The known arrangements, however, do not cater for automatic ladjustments of the reversing elements, and hence no automatic adaptation of the carriage path to the width of the knitting being produced.

Other and further objects, features and advantages of the invention will be apparent to those skilled in the art from the ensuing description and illustration of a preferred example or embodiment of a machine according to the invention. I have set forth with particularity in the appended claims those novel features and relationships which I consider characteristic of my invention, but the invention itself, including its operation, will best be understood by those skilled in the art from the following description taken with reference to the accompanying diagrammatic drawings which show only so much of an exemplary ymachine as is necessary to enable those skilled in the art to fully understand and practice the invention. In the drawings:

FIGURE l is a fragmentary general perspective view showing within one and the sa-me fiat knitting machine, two pairs of knitting units or sections arranged in accordance with this invention, and

FIGURE 2 is a diagrammatic prespective view illustrating various drive and control elements of the machine.

Like parts are designated by similar reference characters throughout the drawing.

Referring to the drawing, the framework of the illustrated machine comprises two side portions, 1, 2 and 1', 2', which are joined together by transverse box-form frame members 3, 3', respectively. The drive mechanisms are housed in the side portions 1, 2 and the box frames 3, 3'. The side portions 1, 2 further `act as supports for parts (not shown) of the superstructure of the machine. Located between the said parts of the superstructure, above the side portions 1, 2 and 1, 2, is an endless drive element 4, e.g., in the form of a chain. This endless drive element 4 passes around two rotary guide components 5 and 6. Thus, where the element 4 is a chain, the com-v ponents 5 and 6 are chain sprockets. The cam box carriages Schl, Sch2, Sch3 and Sch4 are adapted to be co-upled to the endless drive element 4. The rotary component 6 is secured upon a shaft 7 which is mounted in the side portion 1, and on the lower end of which is provided a second sprocket 8. An endless chain is passed both around the sprocket 8 and also around a further sprocket 9 accommodated in the side portion 2.

The chain 10 is driven back and forth by a mechanism converting rotary motion into a reversible axial motion of a practically infinitely variable extent. A detailed example of such a mechanism is disclosed in U.S. Patent No. 2,940,322, issued June 14, 1960, to J. Uhing. Since the specific structural details of the mechanism are known in the art and are not in themselves a feature of this invention, the disclosure of this prior patent is merely incorporated herein by reference, together With the following brief description. The mechanism includes `a drivable rotary shaft, indicated by the numeral 12 in each of FIG- URES l and 2. Movable back and forth along the shaft 12 is a ring casing 11 which is coupled to the chain 10. Within the casing 11 is at least one pair of relatively rotatable concentric rings mounted one within the other with a ball bearing race between them. These concentric rings surround the shaft 12 and can be disposed in a plane inclined with respect to the shaft axis. The internal diameter of the inner ring, which latter bears on the rotating shaft 12, is larger than the diameter of the said shaft. The larger, i.e., outer ring, of the two is provided at diametrically opposed points with trunnions or pintles which are mounted in bearings formed in the casing 11. Associated with one of the mounting points is a spring which urges the inner ring into closer contact with the Shaft 12. Thus with the shaft rotating unidirectionally, the inner one of the concentric rings rotates together with it and relatively to the outer ring. By virtue of the axis of rotation of the shaft and the inner ring being relatively inclined, a force acting parallel to the shaft axis is produced and causes the casing 11 (coupled to the chain 10 as aforesaid) to be moved along the shaft. Means of any suitable form are provided for automatically varying the plane containing the concentric rings. By turning the rings so that they occupy a plane perpendicular to the axis of the rotating shaft, the mechanism will idle so that the casing 11 stops moving; but by causing the plane of the rings to incline in the opposite direction, the direction of travel of the casing along the shaft is reversed. The angle of the inclination of this plane (in either direction) relatively to the axis of the shaft 12 determines the speed of liner movement of the casing 11. Consequently, by appropriate adjustments of the concentric rings, the direction as well as the speed of movement of the chain 10 can be infinitely adjusted. In the specific example illustrated, reversal of the ring casing 11 is effected through the medium of a double-armed reversing lever 13 (FIG- URE l) which cooperates with two adjustable and suitably profiled reversing plates 14, 14. These plates 14, 14 are so formed on their undersides as to present tapped nuts which are mounted on a rotary adjusting screw 1S. Through the medium of la pair of intermesh bevel gears 16, 17 the screw 15 is connected to an indexing or control shaft 18. The drive for this indexing or control shaft 18 is in effect derived from the patterning device 19 which is mounted on the side portion 1. The operation of the individual control elements is effected through the below described means.

The drive spindle y12 of the ring gear housed in the casing 11 is driven by an electric motor (not shown). The speed of this shaft is regulated by the patterning device 19 through conventional structures and arrangements well known in the art. The ring casing 11 accordingly is moved back and forth at a predetermined speed, the movements being transmitted to the endless drive element 4 via the drive chain 10 and thereby causing the back and forth movements of the cam carriages Schl, Scl12, Sch3 and Sch4. Simultaneously with the endless element 4 being driven through the shaft 7 and the rotary component 6, a shaft 22, having secured thereon a cam or eccentric 23, is also driven through the intermeshed spur gears 20, 2'1 (see FIGURE 2). The cam or eccentric 23 is so formed and arranged that its lowest point is in contact with a roller 24 of an indexing linkage 24 whenever each of the cam carriages Schl, Sch2, Sch3 and Sch4 is situated in the middle of its stroke. Since the periphery of the cam or eccentric 23 rises symmetrically on both sides of its lowermost point, the result is that the stroke and timing of the indexing linkage 24 is the same irrespective of the direction of turning of the shaft 7. The indexing movement is terminated as soon as the roller 24 engages a concentric portion of the cam or eccentric 23. Since this concentric portion subtends the major part of the turning angle of the cam or eccentric 23, the linkage 24 remains in the rest position for a substantial period of time, so that in conjunction with the movement of the intermeshed spur gears 20, 21 a long carriage movement can be accomplished before the next change both in the direction of movement of the drive element 4 and in the direction of turning of the cam or eccentric. The reciprocatory control movements of the linkage 24 effected by the cam or eccentric 23 are employed in known manner for operating the pattern device 19, from which all reversals in the machine are initiated. Thus in the particular mechanism illustrated by way of example in FIGURE 2, the linkage 24 is represented as being a pawl-actuating member having associated therewith two pawls 25, 25' arranged to be controlled from the patterning device 19. This control is such that at any one time only one of the pawls is engaged with a ratchet wheel 26 secured on the indexing shaft 18. Accordingly, the indexing shaft 18 performs on each indexing movement a part turn in the clockwise or counterclockwise direction. The shaft 18 can thus be regarded as forming a component part of the patterning device indicated at 19.

As will be seen in FIGURE 2, a screw-threaded spindle 29 is rotated in accordance with the turning direction of the indexing shaft '18 through t-he medium of a pair of intermeshed bevel gears 27, 28, one of which is rigidly secured upon the said shaft. The screw-threaded spindle 29 moves an adjusting nut 30 which is connected, by means of a bar or rod 3.1, with a slide 32 in which are mounted individually movable shifting elements or abutment pins 34 for the cam box actuation in known manner. These pins are brought into working positions according to the pattern. Accordingly, the shifting elements or abutment pins 34 also are adjusted in accordance with the length of stroke of the cam carriages through the indexing or control shaft 18. Rods 35, which are arranged in the longitudinal direction of the machine and extend through the slide 32, serve for actuating the abutment pins 34. To this end each of the actuating rods 35 is furnished at one end with a lever 36 which is connected to the patterning device 19 through a connecting element 37. Whenever this connecting element 37 is operated, the corresponding actuating rod 35 is turned to cause, through a cam not illustrated in the drawing, the relevant abutment pin 34 to lift.

A further pair of intermeshed bevel gears 38, 39 serve to drive a screw-threaded spindle 40 on which are mounted axially adjustable nuts, one of which is shown n FIG- URE 2 and designated by reference character 41. Each such nut is connected, as shown, with a thread guide limiter, one of which is shown in FIGURE 2 `at 42. The screw-threaded spindle 40 may, as shown, also be provided with an adjustable member 43 which, in conjunction with members 44, serves to initiate relative movement of the conventional bar carrying the draw down hooks necessary for the start of either a new, or a widened portion of, knitted fabric. These parts, however, form no part of the invention, and accordingly are not described in detail.

From the immediately foregoing description, it will be appreciated that the movements of the thread guides and the timing of the bar carrying the draw down hooks can all be adapted to the length of the stroke of the cam carriages.

A still further pair of intermeshed bevel gears 45, 46 form a drive connection between the indexing shaft 18 and a screw-threaded spindle 47. A small electric motor 48 which can rotate selectively either in the clockwise or in the counterclockwise direction is coupled to the screwthreaded spindle 47. Mounted for movement axially along the spindle 47 is a nut 50` which is provided with a contact nose 49. Normally this nose is disposed in a neutral position between and clear of the opposed ends of two aligned contact bars 51, 52. Thus whenever the indexing shaft 18 is caused by the patterning device 19 to make a partial turn in either direction, the nut will move correspondingly until the relevant side of its nose 49 makes contact with the opposed end of the appropriate one of the two contact bars 51, 52. However, these contact bars are so electrically connected with the electric motor 48 that whenever the nose 49 makes contact with either of the said bars, the motor will be energized to drive the spindle 47 in the reverse direction to that in which it was turned by the indexing shaft 18, thereby restoring'tlhe nose 49 to its neutral position and at the same time turning back the indexing shaft 18, to return all of the hereinbefore described control elements (the plates 14, 14', the slide 32and the thread guide limiters 42) to their initial positions when the machine has been set to produce knitted fabric of the required smallest or largest width. The motor drive to the spindle 47 is interrupted as soon as the nut 50 has been moved sufficiently far to centralize its nose 49 between the opposed ends of the contact bars 51, 52.

If during the knitting operation the patterning device 19 dictates that neither of the indexing pawls 25, 25 shall be in the working position, the indexing shaft 18 will then remain stationary so that there are no adjustments of the various elements. Furthermore, it is also possible to provide the screw-threaded spindles 15, 29, 40 and 47 with clutches or releasable couplings so controlled by the patterning device 19 that these spindles can be selectively driven from the indexing shaft 18. In this way desired adjustments can be selectively eected each turn of the indexing shaft.

Finally, it is also of course possible to use in place of the herein described ring drive for driving the chain 10, any appropriate alternative form of drive which is capable of imparting a reciprocatory movement with an intinitely variable drive.

Having thus described and illustrated a preferred embodiment of my invention in the manner required by the patent statutes, I claim:

1. An automatic flat knitting machine comprising at least two knitting units arranged one behind the other as Viewed transversely of their lengths, each knitting unit having a cam carriage; means defining a common endless driving element passing around two spaced rotary guide components, the cam carriages being connected to the common endless driving element on respectively opposite sides of said rotary guide components for movement therewith along the knitting units; drive means for selectively imparting to said driving element a reciprocatory motion of selectively and substantially infinitely variable stroke length and stroke speed; a plurality of control means for controlling the stroke length and knitting operations of the knitting units to inuence the knitting of the pieces of fabric being produced; and patterning means common to all knitting units and operatively connected to said drive means for effecting displacements of said control means longitudinally of the machine and for operating said control means in a desired manner.

2. An automatic fiat knitting machine as set forth in claim 1 comprising more than two knitting units, the knitting units being arranged one behind and one beside another.

3. A machine as set forth in claim 2 wherein said control means include elements for reversing cams in the cam systems of the respective cam carriages, means supporting said elements in groups for automatic adjustment in the longitudinal direction of the knitting machine by said patterning means in accordance with the prevailing length of stroke of the cam carriages, and rotatable actuating rods controlled by said patterning means for operating said elements.

4. A machine as set forth in claim 1 wherein said control means include a screw-threaded spindle mounted in driving connection with and for bi-directional rotation by said patterning means, a contact nut mounted on said spindle for axial movement therealong upon rotation of the spindle, an electric motor for selectively rotating said spindle in either direction, two electrical contact members axially spaced from each other adjacent said spindle on axially opposite sides of said contact nut and in the axial path of said contact nut for actuating said electric motor to rotate said spindle in a sense to return said contact nut to a central position between said electrical contacts whenever said contact nut contacts one of said electrical contacts following rotation of said spindle by said patterning means, thereby rotating the spindle, and consequently the patterning means, in an opposite sense and amount relative to the rotation imparted to said spindle by said patterning means.

5. An automatic flat knitting machine comprising at least two flat knitting units arranged one behind the other, each knitting lunit having a cam carriage; and endless drive element to which said cam carriages are connected for movement therewith along the knitting units, said endless drive element comprising an elongate flexible member extending in a closed loop around two rotary guides which are spaced from each other longitudinally of the machine, one of the cam carriages being connected to the portion of the flexible member which extends tangentially between the rotary guides on one side thereof and the other cam carriage being connected to the portion of the flexible member which extends tangentially between the rotary guides on the other side thereof; drive means for selectively reciprocating said exible member and said cam carriages back and forth between said rotary guides at selectively variable speeds and reciprocatory strokes; a patterning device; and indexing shaft; and indexing linkage driven by said drive means and controlled by said patterning device for selectively rotating said indexing shaft upon reciprocatory movement of said cam carriages; and stroke adjusting means controlled by said indexing shaft for selectively varying the stroke of said cam carriages in response to rotation of said indexing shaft.

6. A machine as set forth in claim 5 further comprising a slide member mounted for movement longitudinally of the machine, means for adjusting said slide member longitudinally of the machine in response to rotational movement of said indexing shaft, individually moveable elements mounted in said slide member for reversing cams in the cam systems of the respective cam carriages, and a plurality of actuating rods extending longitudinally of the machine through said slide member and controlled by said patterning device for actuating said individually movable elements.

7. A machine as set forth in claim 6 further comprising a plurality of thread guide limiters, and means for moving said limiters longitudinally of the machine in response to rotation of said indexing shaft.

8. A machine as set forth in claim 6 further comprising means responsive to rotation of the indexing shaft in either direction for automatically rotating the indexing shaft in the opposite direction and in a substantially corresponding amount to return said stroke adjusting means and said slide member to their initial positions.

References Cited UNITED STATES PATENTS FOREIGN PATENTS Germany.

MERVIN STEIN, Primary Examiner.

RONALD FELDBAUM, Assistant Examiner.

U.S. Cl. X.R. 

